US3827271A

US3827271A - Die holding device in an indirect extrusion machine

Info

Publication number: US3827271A
Application number: US00302507A
Authority: US
Inventors: S Kishino; H Amano; T Abe; R Tamura
Original assignee: Japan Steel Works Ltd
Current assignee: Japan Steel Works Ltd
Priority date: 1971-11-25
Filing date: 1972-10-31
Publication date: 1974-08-06
Anticipated expiration: 1991-08-06
Also published as: JPS5138317B2; JPS4857871A

Abstract

A die in an indirect extrusion machine is secured to the stem of the machine at its free end through a die gripper secured to the free end of the stem by such means as screwing and the gripper is adapted to snugly receive the die without allowing it to shift axially.

Description

United States Patent [191 Kishinn et al.

DllE HOLDING DEVTCE llN AN INDIRECT EXTRUSION MACll-llNE lnventors: Slaunji Kishino; Takahiro Abe, both of Muroran; Reishi 'lamura, Noboribetsu; liliroslii Ammo, Muroran, all of Japan Japan Steel Worlrs Ltd, Tokyo, Japan Filed: Get. 31, 1972 Appl. No.: 302,507

Foreign Application Priority Data Assignee:

Nov. 25, 1971 Japan ..4694135 US. Cl 72/253, 72/253 A, 72/481 lnt. Cl. B2lc 23/00 Field 0i Search 72/481, 253, 254

References Cited UNITED STATES PATENTS 10/1960 Swanson 72/253 [111 3,827,271 [45 1 Aug. 6, 1974 3,522,721 8/1970 Whiting ..72/2S5 3,541,831 11/1970 Simomon ..72/253 Primary Examiner-Charles W. Lanham Assistant Examiner-Robert M. Rogers Attorney, Agent, or Firm-Wenderoth, Lind & Ponack [5 7] ABSTRACT A die in an indirect extrusion machine is secured to the stern of the machine at its free end through a die gripper secured to the free end of the stem by such means as screwing and the gripper is adapted to snugly receive the die without allowing it to shift axially.

5 Claims, 8 Drawing Figures PATENTEB W8 5 I974 3. 827, 2 7 1 FIG. 1 PRIOR ART BACKGROUND OF THE INVENTION This invention relates to an improvement in an indirect extruding machine, and more particularly to a die holding device in the indirect extruding machine.

In an indirect metal extruding machine, it is necessary without exception to mount a die for extrusion at the forward end of the elongated hollow stem of the machine. Accordingly, it is conventional that, as shown in FIG. I, an elongated hollow stem 3a rigidly fixed at its base portion by a stem holder la and a stem stopper 2a mounts the die 4a by inserting its projection in a recess provided at the forward portion of the stem. However, in such a mounting means, the die must be dismounted from the stem every time the extrusion of a billet is completed in order to remove the unextruded butt of the billet, and it is also necessary to mount another die to the stem for the next extrusion. For this procedure, in a small capacity extruding machine, it is usual to manually mount the die to the stem, but this is hard work which reduces productivity. Furthermore it also requires a number of dies, which is uneconomic. Moreover, manual operation becomes difiicult as the capacity of an extruding machine becomes larger because the weight of the die becomes so heavy that manual mounting of the die becomes difficult. Accordingly a die mounting apparatus is necessary. However, since such an apparatus is very large, being provided with a grip mechanism and a long arm to grasp the die, the cost of the equipment becomes high and if the apparatus breaks down productivity is seriously affected.

Alternatively, another die mounting means is known, as shown in FIG. 2, by which the stem 3a and the die 4a have corresponding formed screw threads so that the die 4a is screwed to the stem 3a. This means is advantageous in that the butt can be processed while the die 4a is still mounted to the stem 311, so that interchanging of the die is no longer necessary. However, when it is necessary to interchange the die in order to produce different extrusion products, since the temperatures of the die 4a and the stem 30. are raised to 200 to 300C, the dismounting of the die is difficult so that it is necessary to wait until it cools before the interchanging of the die can take place, resulting in a waste of time. Further, when the screw thread of the die is damaged, itis impossible to use the die, so that the life of the die may be shortened. As abovesaid, the hitherto known means for mounting a die to the stem of the indirect extrusion machine have many disadvantages, so notwithstanding the fact that the indirect extrusion method has basically many advantages comparing with a direct extrusion method, an indirect extrusion machine embodying the former method has not yet generally been adopted in the art.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a die holding device in an indirect extrusion machine which can eliminate all of the disadvantages inherent to the conventional die mounting means as described above.

The die holding device of the present invention comprises a die grip means to be mounted to the stem of an indirect extrusion machine, whereby the die is mounted to the stem by securing the die to the die grip means.

BRIEF DESCRIPTION OF THE DRAWINGS This and other objects of the present invention will become more apparent to those skilled in the art when considered in reference to the following detailed description and in light of the accompanying drawings, wherein:

FIG. I is an elevational, sectional view showing a conventional means for mounting the die to the stem of an indirect extruding machine;

FIG. 2 is an elevational partial sectional view showing another conventional means for mounting the die to the stem;

FIG. 3 is an elevational, sectional view of an embodiment of a die holding device in accordance with the present invention;

FIG. 4 is a view similar to FIG. 3 showing an alternative embodiment of the present invention;

FIG. 5 is an elevational, sectional view of the die gripper shown in FIG. 3;

FIG. 6 is a side elevational view of the die gripper shown in FIG. 5;

FIG. 7 is an elevational, sectional view of the die gripper providing a die integrally in accordance with the present invention; and

FIG. 8 is an elevational, sectional view of the die gripper combined with a die in accordance with the present invention.

DESCRIPTION OF PREFERRED EMBODIMENTS As shown in FIG. 3, a hollow stem 3 of an indirect extrusion machine is rigidly secured to the stern holder 1 by a stem securing ring 2 at its tapered base portion, and a die gripper 5 is secured to the stem 3 at its forward end. In order to secure the die gripper 5 to the stem 3, the gripper 5 is provided with a screw thread 7 at the center of one of its end surfaces and a pipe 8, provided with threads at each end, is put through the hole of the hollow stem 3, whereby one of the threads of the pipe 8 is screwed to the threaded end of the die gripping means, while the other of the threads is screwed by a nut a to fasten the pipe 8 to the stem 3. In this case, pins 10 are provided at the free end of the hollow stem 3 for centering the die gripper 5. Otherwise, as shown in FIG. 4, the die gripper 5 may be secured to the free end of the hollow stem 3 by screw threads 7' located on both of them. However, his preferable to secure the die gripper 5 to the hollow stem 3 by the pipe 8 to give it more strength when it is desired to prevent the machining of the screw thread on the stem 3 because securing the die gripper to the pipe 8 makes it possible to give a larger contact area between the hollow stem 3 and the die gripper 5, which increases the strength of the assembly.

Further, the die gripper 5 has a semi-circular projection 11 at its forward end, as shown in FIGS. 5 and 6. This projection 11 engages in a circular groove 12 provided around the outer periphery of the die 4 as shown in FIG. 7 so that the axial displacement of the die 4 is prevented after it is mounted to the die gripper 4.

The die 4 may have a solid construction as shown in FIG. 7, but, in instances, where the shapes of the extruded objects vary frequently, a combined type die is preferable. This combined type die comprises a die ring 13 similarly provided with a circumferential groove 12 at its outer periphery as shown in FIG. 8, into which a changeable die 4 and die backer 14 are inserted.

As explained above, according to the present invention, since a die can be repeatedly used continuously, there is no need to mount the die every time extrusion takes place as in the conventional means, and the preparation of a plurality of dies is also not required, which makes the present invention economic.

Further, since the die can snugly fit the bottom curved surface of the die gripper by the mere insertion of the die into the die gripper so that the die is stably held by the gripper, mounting and dismounting of the die are very simple. Moreover, since no threading of the die for its mounting to the stem is required, the need to discard the die because of damage of its threads is eliminated.

Further, when the die gripper is secured to the stem by means of the pipe passed through it, the stem is not required to be threaded so that it has an advantageously long life.

In order to show the effect of the present invention with some figures, experiments were carried out using an indirect extruding machine having a capacity of some 1,000t operating at an extrusion ratio of 90, with billet dimension of 120 mm(diameter) X 600 mm(length) and using aluminium of series of AA. 6,000 as the material to be extruded.

The results of the experiments are shown in the Table.

one cycle Note: In the above Table, A shows the results when the die was mounted by the conventional means. and B shows the results when the die was mounted through the die holding device according to the present invention,

It will be appreciated that, as shown in Table, by means of the die holding device of the present invention, productivity is increased by about 25 percent compared with the conventional die mounting means. In addition, since in the case of A, an operator exclusively engaged in mounting of die is necessary as well as a machine operator, the present invention has the advantage of requiring fewer operators.

While the invention has been shown and described with reference to preferred embodiments thereof it will be apparent that other changes and modifications can be made in the present invention and therefore it is understood that all changes, equivalents, and modifications within the spirit and scope of the present invention are here meant to be included in the appended claims.

What is claimed is:

1. In an indirect extruding machine having a stem holder, a stem secured at one end thereof to the stem holder and the stem having a threaded opposite end, the improvement comprising a hollow die grip member having a threaded end and an end opposite thereto, said threaded end adapted to be connected to said threaded opposite end of said stem and having a semicircular projection extending outwardly from said opposite end and having an inwardly extending lip at the end of said semicircular projection, said hollow die grip member adapted to snugly receive a corresponding die within said semicircular projection.

2. In an indirect extruding machine having a stern holder, a stern secured at one end thereof to the stem holder and the stem having a threaded opposite end, the improvement comprising a hollow die grip member having a threaded end and an end opposite thereto, said threaded end adapted to be connected to said threaded opposite end of said stem and having a semicircular projection extending outwardly from said opposite end and having an inwardly extending lip at the end of said semi-circular projection, and a die having a groove provided around the periphery thereof adapted to engage said lip of said semi-circular projecting, whereby said die is snugly supported within said semi-circular projection.

3. A die mounting device and die combination in an indirect extruding machine having a stem holder comprising: a hollow stem secured at one end thereof to the stem holder of said indirect extruding machine; a pipe member positioned within said hollow stern and having threaded opposite peripheral end portions, one end portion thereof being secured to said stem holder, the other end portion thereof extending beyond said hollow stem; a hollow die grip member having one threaded end and an opposite end, said threaded end being connected to said extending end of said pipe member, said hollow die grip member having a semicircular projection extending outwardly from said opposite end and having an inwardly extending lip at the end of said semi-circular projection, said die grip member adapted to snugly receive a die within said semicircular projection; and a die having a groove provided around the periphery thereof and adapted to engage said lip of said semi-circular projection, whereby said die is snugly supported therein.

4. The device of claim 3, further comprising a plurality of pins connected between said hollow die grip member and said stem for centering said hollow die grip member relative to said stem and further comprising a bolster member adapted to be interposed between the opposite end of said hollow die grip member and said die.

5. A die for use in anindirect extruding machine having a stem holder, a stem secured at one end thereof to the stem holder and the stem having a threaded opposite end, a threaded hollow die grip member having a threaded end and an end opposite thereto, said threaded end of said die grip member adapted to be connected to said threaded opposite end of said stem and said opposite end of said threaded hollow die grip member having a semi-circular projection extending outwardly from said opposite end and having an inwardly extending lip at the end of said semi-circular projection, said die comprising a body having a groove provided around the periphery thereof and adapted to engage said lip of said semi-circular projection, whereby said die is snugly supported therein.

Claims

1. In an indirect extruding machine having a stem holder, a stem secured at one end thereof to the stem holder and the stem having a threaded opposite end, the improvement comprising a hollow die grip member having a threaded end and an end opposite thereto, said threaded end adapted to be connected to said threaded opposite end of said stem and having a semi-circular projection extending outwardly from said opposite end and having an inwardly extending lip at the end of said semicircular projection, said hollow die grip member adapted to snugly receive a corresponding die within said semicircular projection.

2. In an indirect extruding machine having a stem holder, a stem secured at one end thereof to the stem holder and the stem having a threaded opposite end, the improvement comprising a hollow die grip member having a threaded end and an end opposite thereto, said threaded end adapted to be connected to said threaded opposite end of said stem and having a semi-circular projection extending outwardly from said opposite end and having an inwardly extending lip at the end of said semi-circular projection, and a die having a groove provided around the periphery thereof adapted to engage said lip of said semi-circular projecting, whereby said die is snugly supported within said semi-circular projection.

3. A die mounting device and die combination in an indirect extruding machine having a stem holder comprising: a hollow stem secured at one end thereof to the stem holder of said indirect extruding machine; a pipe member positioned within said hollow stem and having threaded opposite peripheral end portions, one end portion thereof being secured to said stem holder, the other end portion thereof extending beyond said hollow stem; a hollow die grip member having one threaded end and an opposite end, said threaded end being connected to said extending end of said pipe member, said hollow die grip membEr having a semi-circular projection extending outwardly from said opposite end and having an inwardly extending lip at the end of said semi-circular projection, said die grip member adapted to snugly receive a die within said semi-circular projection; and a die having a groove provided around the periphery thereof and adapted to engage said lip of said semi-circular projection, whereby said die is snugly supported therein.

5. A die for use in an indirect extruding machine having a stem holder, a stem secured at one end thereof to the stem holder and the stem having a threaded opposite end, a threaded hollow die grip member having a threaded end and an end opposite thereto, said threaded end of said die grip member adapted to be connected to said threaded opposite end of said stem and said opposite end of said threaded hollow die grip member having a semi-circular projection extending outwardly from said opposite end and having an inwardly extending lip at the end of said semi-circular projection, said die comprising a body having a groove provided around the periphery thereof and adapted to engage said lip of said semi-circular projection, whereby said die is snugly supported therein.